Phenthiazine compounds



rates '5 2,972,612 Patented Feb. 21, 1961 The compound of the present inventionthereforepre: sents advantages (viz. absence of side-efiectslover the, aforesaid compounds of related chemicalstructure which make it very suitable for clinical use as a specific-antig histaminic. V

The' unexpected properties of thecompound of the, invention are, demonstrated by the following tests;

(a.)' TOXICITY (0) THE SCHAUMAQINYN TEST FOR ANTI- PHENTHIAZINE COMPOUNDS Robert Michel Jacob, Ablon-sur-Seine, and Jacques Georges Robert, Paris, France,,assignors to Speietedes Usines Chimiques RhoneToulenqParis, France, a corporation of France No Drawing. Filed Apr. 1,1958, Ser. No..7 2 5,;4;Sl9v Claims priority, application Great Britain May 13, 1955 3 Claims. (Cl. 260-243) This invention relates to anti-histaminic drugs and totherapeutic compositions containing the same, this application' being .a continuation-in-part of applicationSerial. No. 617,235, filed on October 22, 1956,'now Patent No. 2,837,518, granted June 3, 1958, itself a continuation-inpart of applications Serial No. 545,103, filed November 4, 2 1955, and i lNo- 9,174,.filed Novem er25, 19.5.5, both of which latter applications were abandoned.

It is known a ar ous. firaininoalkyl. phenthiaz nes Extensive re- Search and me tat onhas shewnhoweven hatbotb .25.-

possess interesting therapeutic properties.

the size of the therapeutic index and the nature of the HISTAMI NIC ACT IVITY" There are determined;

(-1) --The' minimum dose of--product,-- expressed in- ./k:-.. (1.... h'h t, therapeutic effect exhibited by.certain compoundsofth s mg g 0 L313 (Roi W m pm of type can radically be changed-(even-eliminated)" by even"" duc'd by hitmine aerosols a small changes in chemical structure... Especiallyis..this (2) The'hmmimurm dose of i in the case with Variations in. thefiiuure'andflcngth offithe rug/kg 5.0.) and (1 .0.) which completelY's'uPPPr esses filiiltiifitiiifiii it?assistants? a e t a It is the object of this invention to provide new'phen- 2 gumeaplgs gp go fie'gurwon ttt thiazine compounds which have a powerful and specific1'""'g z z i ggiig z giff p guts. m anti-histaminic activity with substantial absence of effects .35 v

j guinea pigs for I 10 minutes againsttbronchospasm,pro;

on the central nervous systernr-It is a further'object off ca a of b n used clinically. whi h is free. .fromsthos 50 side effectsl In our application Serial No. 617,235 we have disclosed inter alia 3-( lO-phenthiazinyl)-2-methyl-l-dimethylaminopropane as a compound combining'both anti-histaminic and central nervous action in a degree greater thanth'at of any cornpoundoi the prior art.. This unusual combination of properties gives this compound certain: valuable clinical uses, butthis, compound cannot satisfactorily be used in circumstances where it is important to avoid action on the central nervous system.

According to the present invention it .has nowbeen unexpectedly discovered that 3-(9:9'-.dioity-l0-phenthi-v azitiyl)-2 methyl l-dimethylaminopropane, which differs infstructureffrorn the compound mentioned above of our application Serial No. 617,235 only in'the presence of 6 two oxygen atoms attached to the sulphur atom of the molecule, possesses (as such or in' the form of a salt) marked anti histaininic activity comparable with that of the above-named compounds, 1-(IO-phenthiazinyU -Z-dimthylaminopropane and 3-(lO-phenthiazinyl)-2-meth'yl- 70 lrdimethylaminopropane, combined with'weaker central nervous activity than either.v .t

' V tretc ed-W re. s's ghti TENTIATION OF HEXOBARBITAL The product to be studied is administered subcutaneously to the test animal (mouse) in a dose. of 20 mg./kg.; thirty minutes later, hexabarbital is intravenouslyxadministered in a dose of 50 mg./kg. The .averageiduration j (a iiYEIAQ I NjMEA UR D is THE Po.

5 of the narcosis in minutes is noted.

(a) sEDATIvE AcTIoN MEAS RE As.

ABILITY TO TRANQUILLIZ E FIGHIING MIQE Two male mice, aged 6rmonths and weighingf'from 30' to,35 g., are brought together. The control animals (untreated) fight in the following 10 seconds.- The treated animals are observed for 20 minutes. ,The time in minutes elapsing before the start of the fight is noted.- This time is multiplied W5 and the percentage of protection is thus obtained:(example: fight after 4 minutes=20% protection-gfight at the end of 20 minutes, or no fight=- -.100% protection). i a The coefiicient of 1% is given to the'controls (fight' in the first 10 seconds). f

5 to 6 pairsper dose are used and the dose whichgives a protection to the treated animals (DE is determined for administration so. and for administration pn.

(f) THE WINTER AND FLATAKERTEST" This testis "described in J. Pharm. Exp.-Th er.;103, :93, (1951). There is determinedgraphically, by comparison with controls, the dose, in mg./kg. which, administered 5 per os 1 /2 hours before the test, reduces the spontaneous TRACTION T sTfiQJ;

orally (DA from effecting a recovery on:a: horizontally The dose which prevents 50% of. themicetreated ANTI-EMETIC ACTIVITY the percentage reduction as compared with the control animals was deduced.

The results obtained are summarised in the following table where I is 3-(9:9-dioxy-l0-phenthiazinyl)-2-methyl l-dimethylaminopropane (the compound of the present invention) and II and III are l-(l-phenthiazinyl)2-dimethylaminopropane and 3-(IO-phenthiazinyl)-2-methyll-dimethylaminopropane, respectively.

thiarinyl)-2-methyl-1-dimethylaminopropane and its therapeutically acceptable salts, in association with a pharmaceutical diluent. In clinical practice the compounds of the present invention will normally be administered orally, in consequence of which the preferred formulations are those of the kind suitable for oral administration.

Preparations for oral ingestion can be liquids or solids or any combination of these forms, such as solutions, suspensions, syrups, elixirs, emulsions, powders or tablets. Pharmaceutical preparations for administration of the active therapeutic agents in unit dose form can take the form of compressed powders (or tablets) or of a powder enclosed in a suitable capsule of absorbable material such as gelatin. These compressed powders (or tablets) can take the form of the active materials admixed with suitable excipients and/or diluents such as starch, lactose,

. stearic acid, magnesium stearate or dextrin.

In yet a further embodiment, the active material may, as such or in the form of a diluted composition, be put up in powder packets and employed as such.

Table Method Products Test Animals Dose, of ArtmgJkg. lninistra tion I II III (a) Toxicity Low (in three days)- Mic {23 igk 33g ggg (b) Antlhlstaminic activity: Bovet- Guinea pigs--- 20 c 1,300 1,200 1,500. Staub test. A s c 0 025 0 0b 1 Guinea pigs--- O2 to AnflmswmmimfivwSchaumanni iii??? 21%.:11: 3328.??13133: 832839.511: ia' (4 test. .Gu1neap1 DEM, p.o 2.5(2h.) 2.0 (411 2mg.(2 11.). (d) Sedagive)i aftion: potentiation of Mice -4.-- 2 5.0 28min min 89 min.

hexo ar ta (e) Sedatlveactionitranquillizing fight- Mice D1250 .c ..'Mnre than 50.. 20.0 3.5. lng mice. lMwe D no More than 50.4. 35.0 9.0, Winter and Flatakertest Mice D io p- More than 80.0. 47.0 3.5. g) Traction test p Mic DA5020 p.0 More than 100.0. 95.0 15.0. (h) Anti-emetic activity Dog 2 0% The results given in this table clearly show that compound I has a high anti-histaminic activity and low toxicity of the same order as those of compounds 11 and III, but has much lower activity in its other physiological actions, such as anti-emetic effect and sedative action.

This highly specific action makes it even more suitable for use clinically as an anti-histaminic than compound 11, up till now very widely used for this purpose.

For therapeutic purposes the compound of the invention may be employed as such or in the form of acid addition salts containing anions which are relatively innocuous to the animal organism in therapeutic doses of the salts by weight of active substance.

(such'as the hydrochloride and'other hydrohalides, phosphate, nitrate, sulphate, maleate, fumarate, citrate, tartrat e, methanesulphonate and ethanedisulphonate) so that the beneficial physiological properties inherent in the base are not vitiated by side-effects ascribable to the anion. Similarly, it may also be employed "in the form of quaternary ammonium salts obtained'by reaction with organic halides (e.g. methyl or ethyl iodide,chloride or bromide or allyl or benzyl chloride or bromide) or The invention is illustrated by the following examples:

EXAMPLE I B-(IO-phen'thiazinyD-Z methyl 1 dimethylaminopropane (11.9 g.) is dissolved with agitation in glacial acetic acid (120cc). Pure sulpuhric acid (d=l.83; 0.5 cc.) is added anda mixture of glacial acetic acid (10 cc.) and hydrogen peroxide (8.5 cc. of a solution containing 38 g. of hydrogen peroxide in cc.) is then run in over 20 minutes. The temperature. rises from 2535 C. and is then kept at 60. C. for .18 hours. The mixture is cooled and Water- (l 50 cc.) is added and, with cooling,...aqueous sodium hydroxide (d=1.33; 220 cc.). The resulting mixture is extracted .With ethyl acetate (3x100 cc.), the solvent is evaporated on a water bath and the residue is recrystallised from heptane (150 cc.). 3-(9z9-dioxy-l0- phenthiazinyl)-2-methyl-l-dimethylaminopropane (7.8 g.) isobtainedyMP. 'C.

1'1" he corresponding hydrochloride prepared in ethyl acetate and recrystallised from a mixture of ethanol and isopropanol melts at 250 C.

5 EXAMPLE II References Cited in the file of this patent Tablets of the formula: UNITED STATES PATENTS 5 5 P g i' 2,512,520 Cusic June 20, 1950 l met y 5 2,519,886 Charpentier Aug. 22, 1950 armnopropane hydrochlonde 0-0112 2,530,451 Charpentier NW 21, 1950 S h of 2,645,640 Charpentier July 14, 1953 0-0300 2,785,160 Jacob et a1 Mar. 12, 1957 i 2,837,518 Jacob et a1 June 3, 1958 Magnesium stearate 0.0030 g. 10 are prepared according to the usual procedure for the FOREIGN PATENTS preparation of tablets for pharmaceutical use. 782,431 Great Britain Sept. 4, 1957 We claim:

1. A member of the class consisting of 3-(9z9-dioxy- OTHER REFERENCES 10-phenthiaziny1)-2-methy1-l-dimethylaminopropane d 15 Viaud: J. Pharmacy and PharmacoL, vol. 6 1954), its therapeutically acceptable acid addition salts. pp 3 1 and 3 4 3 y- -P y Y Kano et al.; Pharm. Bull (Tokyo), vol. 5 (June 1957), ylarninopropane. pp. 389-393.

3. 3 (9:9-dioxy-10-phenthiaziny1)-2-methy1-1-dimethylaminopropane hydrochloride. 20 

1. A MEMBER OF THE CLASS CONSISTING OF 3-(9:9-DIOXY10-PHENTHIAZINYL)-2-METHYL-1-DIMETHYLAMINOPROPANE AND ITS THERAPEUTICALLY ACCEPTABLE ACID ADDITION SALTS. 